Display device and method for manufacturing the same

ABSTRACT

Provided is a display device, including: a sealing member including an opening and surrounding a space defined by a pair of light transmissive substrates; an end seal for closing the opening of the sealing member to form an encapsulation space; oil filled in the encapsulation space; a spacer for maintaining an interval between the pair of light transmissive substrates; a shutter; a drive portion arranged in the oil, for mechanically driving the shutter; and a wall portion formed on at least one of opposed surfaces of the pair of light transmissive substrates. The wall portion includes apart arranged at a position interrupting a shortest path between the opening of the sealing member and a display region. The wall portion is made of a material forming the spacer, the shutter, and the drive portion.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority from Japanese application JP2011-124625 filed on Jun. 2, 2011, the contents of which are herebyincorporated by reference into this application.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a display device and a method ofmanufacturing the same.

2. Description of the Related Art

A micro-electro-mechanical system (MEMS) display is a display expectedto replace a liquid crystal display (see Japanese Patent ApplicationLaid-open No. 2008-197668). This display differs from a liquid crystalshutter type display utilizing polarization, and displays an image byopening and closing a light transmissive window using a mechanicalshutter system. A shutter is formed of a thin film. Vertical andhorizontal sizes of one shutter forming one pixel are in the order ofseveral hundred micrometers, and a thickness thereof is in the order ofseveral micrometers. One shutter is opened/closed to enable ON/OFFoperation for one pixel. The shutter is operated by an electrostaticattractive force.

The shutter is arranged in a space surrounded by a sealing memberbetween a pair of light transmissive substrates, and the space is filledwith oil. The oil is used to prevent a spring for driving the shutterfrom sticking, and to reduce a difference in optical refraction indexwith respect to the light transmissive substrates.

The oil is injected from an injection port corresponding to an openingof the sealing member, and the injection port is encapsulated by a resinafter the oil injection. For high-speed open/close operation of theshutter, oil having low viscosity is desired, but in this case, thespeed of oil when passing through the injection port increases to causea problem of damaging the shutter.

SUMMARY OF THE INVENTION

The present invention has an object to reduce damage on a mechanicalshutter when oil is injected to fill a cell in which the mechanicalshutter is arranged.

(1) According to an exemplary embodiment of the present invention, thereis provided a display device, including: a pair of light transmissivesubstrates arranged at an interval; a sealing member which is broughtinto close contact with opposed surfaces of the pair of lighttransmissive substrates, the sealing member including an opening andsurrounding a space defined by the pair of light transmissivesubstrates; an end seal for closing the opening of the sealing member,thereby encapsulating the space to form an encapsulation space; oilfilled in the encapsulation space; a spacer, which is arranged in theoil, for maintaining the interval between the pair of light transmissivesubstrates; a light shielding film formed on one of the pair of lighttransmissive substrates, the light shielding film including an apertureportion; a shutter arranged in the oil; a drive portion arranged in theoil, for mechanically driving the shutter so as to control passage andblocking of light through the aperture portion; and a wall portionformed on at least one of the opposed surfaces of the pair of lighttransmissive substrates. The spacer, the shutter, and the drive portionare arranged in a display region for displaying an image depending onpresence/absence and intensity of the light passing through the apertureportion. The wall portion includes a part arranged at a positioninterrupting a shortest path between the opening of the sealing memberand the display region. The wall portion is made of a material formingthe spacer, the shutter, and the drive portion. According to theexemplary embodiment of the present invention, when the oil is injectedfrom the opening of the sealing member, the flow of the oil can beweakened by the wall portion, and hence it is possible to reduce thedamage on the shutter. Further, the wall portion is made of a materialforming the spacer, the shutter, and the drive portion, and hence whenthose members are simultaneously formed, it is possible to avoidincrease of the number of manufacturing steps.

(2) In the display device according to Item (1), the wall portion may bebrought into close contact with the opposed surfaces of the pair oflight transmissive substrates.

(3) In the display device according to Item (2), the wall portion may bearranged so as to surround the display region, and the wall portion mayinclude a slit formed at a position except for the position interruptingthe shortest path.

(4) In the display device according to Item (2), the wall portion may beformed so as to linearly extend between the opening and the displayregion to pass the position interrupting the shortest path.

(5) In the display device according to Item (4), the wall portion mayextend along a plurality of parallel straight lines, and parts of thewall portion extending along the plurality of parallel straight lines,respectively, may each include a slit.

(6) According to an exemplary embodiment of the present invention, thereis provided a method of manufacturing a display device, including:assembling an empty cell so as to include: a pair of light transmissivesubstrates arranged at an interval; a sealing member which is broughtinto close contact with opposed surfaces of the pair of lighttransmissive substrates defined by the pair of light transmissivesubstrates, the sealing member including an opening and surrounding aspace; a spacer, which is to be arranged in oil, for maintaining theinterval between the pair of light transmissive substrates; a lightshielding film formed on one of the pair of light transmissivesubstrates, the light shielding film including an aperture portion; ashutter arranged in the space; a drive portion arranged in the space,for mechanically driving the shutter so as to control passage andblocking of light through the aperture portion; and a wall portionformed on at least one of the opposed surfaces of the pair of lighttransmissive substrates, the spacer, the shutter, and the drive portionbeing arranged in a display region for displaying an image depending onpresence/absence and intensity of the light passing through the apertureportion, the wall portion including a part arranged at a positioninterrupting a shortest path between the opening of the sealing memberand the display region; and injecting the oil into the empty cell fromthe opening of the sealing member. The assembling of the empty cellincludes simultaneously forming the spacer, the shutter, the driveportion, and the wall portion in a plurality of processes includingforming of a thin film and etching. The injecting of the oil includesinjecting the oil from the opening of the sealing member under a statein which an inside of the space is set to have an atmospheric pressurelower than an atmospheric pressure of an outside. According to theexemplary embodiment of the present invention, when the oil is injectedfrom the opening of the sealing member, the flow of the oil can beweakened by the wall portion, and hence it is possible to reduce thedamage on the shutter. Further, the wall portion is formedsimultaneously when forming the spacer, the shutter, and the driveportion, and hence it is possible to avoid the increase of the number ofmanufacturing steps.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIG. 1 is a side view of a display device according to an embodiment ofthe present invention;

FIG. 2 is a plan view of the display device illustrated in FIG. 1;

FIG. 3 is a perspective view of a shutter and a drive portion thereof;

FIG. 4 is an enlarged view of a cross-section taken along the line IV-IVof the display device illustrated in FIG. 2;

FIG. 5 is a plan view illustrating a part inside an empty cell;

FIG. 6 is a sectional view taken along the line VI-VI of the structureillustrated in FIG. 5;

FIG. 7 is a view illustrating a step of forming a second wall portion, asecond spacer portion, and a second anchor portion;

FIG. 8 is a view illustrating the step of forming the second wallportion, the second spacer portion, and the second anchor portion;

FIG. 9 is a view illustrating the step of forming the second wallportion, the second spacer portion, and the second anchor portion;

FIG. 10 is a view illustrating the step of forming the second wallportion, the second spacer portion, and the second anchor portion;

FIG. 11 is a view illustrating a step of injecting oil into the emptycell;

FIG. 12 is a view illustrating the step of injecting the oil into theempty cell;

FIG. 13 is a view illustrating the step of injecting the oil into theempty cell;

FIG. 14 is a view illustrating the step of injecting the oil into theempty cell;

FIG. 15 is a view illustrating a modified example of the display deviceaccording to the embodiment of the present invention; and

FIG. 16 is a view illustrating another modified example of the displaydevice according to the embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, an embodiment of the present invention is described withreference to the drawings.

FIG. 1 is a side view of a display device according to the embodiment ofthe present invention. The display device includes a pair of lighttransmissive substrates 10 and 12 (for example, glass substrates). Thepair of light transmissive substrates 10 and 12 are arranged so as to beopposed to each other at an interval (see FIG. 4). FIG. 2 is a plan viewof the display device illustrated in FIG. 1. In FIG. 2, the upper lighttransmissive substrate 12 is represented by a virtual line to show theinner structure. As illustrated in FIG. 2, a plurality of (large numberof) shutters 14 are provided on the lower light transmissive substrate10.

FIG. 3 is a perspective view of the shutter 14 and a drive portionthereof. The shutter 14 is made of an inorganic material such assemiconductor or a metal, and is a plate including an aperture portion16. Light is allowed to pass through the aperture portion 16, and isblocked at a part other than the aperture portion 16. The apertureportion 16 has a shape long in one direction. Note that, as illustratedin FIG. 1, light is supplied from a backlight unit 18 lying under thelight transmissive substrate 10.

The shutter 14 is supported by a first spring 20 to be suspended abovethe light transmissive substrate 10. A plurality of (four in FIG. 2)first springs 20 support the shutter 14. The first spring 20 is fixed tothe light transmissive substrate 10 by a first anchor portion 22.Specifically, the first anchor portion 22 is provided on first wiring 24formed on the light transmissive substrate 10, and the first anchorportion 22 and the first wiring 24 are electrically connected to eachother.

The first spring 20 is made of an elastically deformable material, andis arranged so as to be deformable in a direction parallel to the platesurface of the shutter 14. Specifically, the first spring 20 includes afirst portion 26 extending in a direction separating from the shutter 14(direction intersecting (for example, orthogonal to) the lengthdirection of the aperture portion 16), a second portion 28 extending ina direction along the length direction of the aperture portion 16outwardly from a center of the aperture portion 16 in the lengthdirection, and a third portion 30 further extending in the directionseparating from the shutter 14 (direction intersecting (for example,orthogonal to) the length direction of the aperture portion 16).Further, as indicated by the arrows in FIG. 3, the shutter 14 issupported by the first spring 20 so as to be movable in the directionintersecting (for example, orthogonal to) the length direction of theaperture portion 16.

The light transmissive substrate 10 is provided with a second spring 34supported by a second anchor portion 32. The second anchor portion 32 isprovided on second wiring 36 formed on the light transmissive substrate10, and the second anchor portion 32 and the second wiring 36 areelectrically connected to each other. The second spring 34 is opposed tothe second portion 28 of the first spring 20 on a side separated fromthe shutter 14 with respect to the second portion 28. When a voltage isapplied to the second anchor portion 32, due to the electrostaticattractive force caused by the potential difference between the secondanchor portion 32 and the second portion 28 of the first spring 20, thesecond portion 28 is attracted toward the second anchor portion 32. Whenthe second portion 28 is attracted, the shutter 14 is also attracted viathe first portion 26 provided integrally with the second portion 28.That is, the first spring 20 and the second spring 34 are provided forconstituting a drive portion 38 for mechanically driving the shutter 14.The drive portion 38 is also made of an inorganic material such assemiconductor or a metal.

FIG. 4 is an enlarged view of a cross-section taken along the line IV-IVof the display device illustrated in FIG. 2. The upper lighttransmissive substrate 12 has alight shielding film 40 formed thereon.An aperture portion 42 is formed in the light shielding film 40. Theabove-mentioned aperture portion 16 of the shutter 14 and the apertureportion 42 of the light shielding film 40 are arranged at positionsopposed to each other. Light is allowed to pass when both of theaperture portions communicate with each other, and light is blocked whenthe aperture portion 42 of the light shielding film 40 is covered due tothe movement of the shutter 14. In other words, the shutter 14 ismechanically driven so as to control the passage and blocking of lightthrough the aperture portion 42 of the light shielding film 40. Oneaperture portion 16 and one aperture portion 42 corresponding to eachother constitute one pixel, and an image is displayed by a large numberof pixels. Therefore, the plurality of (large number of) shutters 14 areprovided. The shutters 14 and the drive portions 38 thereof are arrangedin a display region (see FIG. 2) which displays an image depending onthe presence/absence and intensity of light passing through the apertureportions 16, 42.

As illustrated in FIG. 4, the pair of light transmissive substrates 10and 12 are fixed at an interval with a sealing member 44. The sealingmember 44 is provided in close contact with opposed surfaces of the pairof light transmissive substrates 10 and 12. Further, as illustrated inFIG. 2, the sealing member 44 includes an opening 46 and is formed so asto surround a space defined by the pair of light transmissive substrates10 and 12. Specifically, the sealing member 44 has a part extendingalong a rectangular edge surrounding a rectangular display region 48.Note that, the pair of light transmissive substrates 10 and 12 also havea rectangular shape so as to correspond to the rectangular displayregion 48. An end seal 50 closes the opening 46 of the sealing member44, thereby encapsulating the space surrounded by the sealing member 44to form an encapsulation space.

As illustrated in FIG. 4, oil 52 (for example, silicone oil) is filledin the encapsulation space. The shutter 14 and the drive portion 38 arearranged in the oil 52. The oil 52 can suppress vibrations caused by themovement of the shutter 14 and the drive portion 38, and also canprevent sticking of the first spring 20 and the second spring 34. Whenthe light transmissive substrates 10 and 12 are made of glass, with useof the oil 52 having a refractive index close to that of glass, throughfilling of the oil 52, it is possible to reduce light reflection at aninterface of the pair of light transmissive substrates 10 and 12.

The display device includes a spacer 54 for maintaining an intervalbetween the pair of light transmissive substrates 10 and 12. The spacer54 is arranged in the oil 52 as well, and is arranged in the displayregion 48 illustrated in FIG. 2. The spacer 54 illustrated in FIG. 4includes a first spacer portion 56 provided on the upper lighttransmissive substrate 12, and a second spacer portion 58 provided onthe lower light transmissive substrate 10, the first spacer portion 56and the second spacer portion 58 being bonded to each other. The firstspacer portion 56 is made of a resin. The second spacer portion 58includes two layers of resin portions 58 a and 58 b, and an inorganicportion 58 c which is made of a semiconductor film or a metal filmcovering the surfaces of the resin portions 58 a and 58 b.

The display device includes a wall portion 60 formed on at least one ofthe opposed surfaces of the pair of light transmissive substrates 10 and12. In the example illustrated in FIG. 4, the wall portion 60 is broughtinto close contact with the opposed surfaces of the pair of lighttransmissive substrates 10 and 12. Specifically, the wall portion 60includes a first wall portion 62 provided on the upper lighttransmissive substrate 12, and a second wall portion 64 provided on thelower light transmissive substrate 10, the first wall portion 62 and thesecond wall portion 64 being bonded to each other. The wall portion 60is made of a material forming the spacer 54, the shutter 14, and thedrive portion 38. In the example illustrated in FIG. 4, the first wallportion 62 is made of a resin. The second wall portion 64 includes twolayers of resin portions 64 a and 64 b, and an inorganic portion 64 cwhich is made of a semiconductor film or a metal film covering thesurfaces of the resin portions 64 a and 64 b.

As illustrated in FIG. 2, the wall portion 60 is arranged so as tosurround the display region 48. Specifically, the wall portion 60 isarranged on the rectangular edge surrounding the rectangular displayregion 48. The wall portion 60 has a part arranged at a positioninterrupting a shortest path between the opening 46 of the sealingmember 44 and the display region 48. That is, at least a part of thewall portion 60 is present so as to interrupt a straight-line pathbetween the opening 46 of the sealing member 44 and the display region48. In other words, at least a part of the wall portion 60 is presentbetween the opening 46 of the sealing member 44 and the display region48. The wall portion 60 includes slits 66 formed at positions except forthe position interrupting the shortest path.

In the example of FIG. 2, the slit is not formed on a straight line ofthe rectangular edge surrounding the rectangular display region 48,which is provided opposed to the opening 46 of the sealing member 44.The wall portion 60 includes a part 60 a extending on the straight line,and a part 60 b extending at an interval from the part 60 a in anorthogonal direction (direction separating from the opening 46 of thesealing member 44). The slit 66 is formed between the part 60 a and thepart 60 b. Further, the slit 66 is formed in the part 60 b itselfextending in the direction separating from the opening 46 of the sealingmember 44. Further, the slit 66 is also formed between the part 60 bextending in the direction separating from the opening 46 of the sealingmember 44 and a part 60 c formed on a side opposite to the opening 46 ofthe sealing member 44 across the display region 48 (that is, a cornerportion). Further, the slit 66 is formed in the part 60 c itself formedon the side opposite to the opening 46 of the sealing member 44 acrossthe display region 48. As described above, the wall portion 60 includesa plurality of slits 66. Through the slits 66, the oil 52 can flow inand out of a region surrounded by the wall portion 60.

The display device has a structure in which an empty cell is filled withthe oil 52. FIG. 5 is a plan view illustrating a part inside the emptycell. FIG. 6 is a sectional view taken along the line VI-VI of thestructure illustrated in FIG. 5. The empty cell includes, as describedabove, the second wall portion 64, the second spacer portion 58, and thesecond anchor portion 32, which are provided on the light transmissivesubstrate 10 arranged on the lower side in FIG. 1. The second anchorportion 32 is made of the same inorganic material (semiconductor or ametal) as the surface layers of the second wall portion 64 and thesecond spacer portion 58. The second anchor portion 32 has a part whichrises three-dimensionally and is suspended from the light transmissivesubstrate 10. The second wiring 36 is present under the second anchorportion 32, and the second wiring 36 and the second anchor portion 32are electrically connected to each other. Note that, the second spacerportion 58 is also arranged on the second wiring 36.

FIGS. 7 to 10 are views illustrating a step of forming the second wallportion 64, the second spacer portion 58, and the second anchor portion32.

As illustrated in FIG. 7, a first resin layer 68 is formed on the lighttransmissive substrate 10 arranged on the lower side in FIG. 1. Forexample, a photosensitive resin such as a photoresist is patterned bylithography, and the photosensitive resin is cured by ultraviolet raysor the like to form the first resin layer 68. The first resin layer 68includes a part forming the lower resin portion 64 a of the second wallportion 64 and the lower resin portion 58 a of the second spacer portion58, and a part for shaping a lower part of the second anchor portion 32.The first resin layer 68 is formed so as to be placed on the secondwiring 36, and is formed so as to avoid an electrical connection portionbetween the second anchor portion 32 and the second wiring 36, that is,formed so that a part of the second wiring 36 is exposed.

As illustrated in FIG. 8, a second resin layer 70 is formed on the firstresin layer 68. The second resin layer 70 is also formed by patterning aphotosensitive resin such as a photoresist by lithography. The secondresin layer 70 includes a part forming the upper resin portion 64 b ofthe second wall portion 64 and the upper resin portion 58 b of thesecond spacer portion 58, and a part for shaping an upper part of thesecond anchor portion 32. The second resin layer 70 is also formed so asto avoid the electrical connection portion between the second anchorportion 32 and the second wiring 36, that is, formed so that a part ofthe second wiring 36 is exposed.

As illustrated in FIG. 9, on the light transmissive substrate 10 and themembers formed thereon (second wiring 36, first resin layer 68, andsecond resin layer 70), an inorganic layer 72 (for example, a-SiN/Alfilm) is formed by chemical vapor deposition (CVD) or sputtering. Theinorganic layer 72 is subjected to etching as illustrated in FIG. 10.The inorganic layer 72 may be a single layer or may include a pluralityof layers. Through the etching, the inorganic portion 64 c of the secondwall portion 64, the inorganic portion 58 c of the second spacer portion58, and the second anchor portion 32 are obtained. Further, the firstresin layer 68 and the second resin layer 70, which are present belowthe second anchor portion 32, are removed, and thus the structureillustrated in FIG. 6 is obtained.

With the same process of forming the second anchor portion 32, theshutter 14, the first anchor portion 22, the first spring 20, and thesecond spring 34 are formed. Further, on the light transmissivesubstrate 12 on the opposite side, the first wall portion 62 and thefirst spacer portion 56 are simultaneously formed (see FIG. 4).

With the steps described above, the spacer 54, the shutter 14, the driveportion 38, and the wall portion 60 are simultaneously formed in aplurality of processes including forming of a thin film and etching.

A method of manufacturing the display device according to thisembodiment includes the above-mentioned steps, and also includes asubsequent step of assembling the empty cell. The empty cell includesthe pair of light transmissive substrates 10 and 12 arranged at aninterval, and a structure present therebetween corresponds to thestructure of the display device described above except that the oil 52is absent. That is, the empty cell is in a state before injection of theoil 52.

FIGS. 11 to 14 are views illustrating a step of injecting the oil 52into the empty cell. In this embodiment, in the step of injecting theoil 52, an inner space is set to have an atmospheric pressure lower thanthat of the outside, and then the oil 52 is injected from the opening 46of the sealing member 44.

Specifically, as illustrated in FIG. 11, an empty cell 74 in which thesealing member 44 surrounds an inner space is prepared. Further, in avacuum chamber 76, a container 78 containing the oil 52 is prepared. Asillustrated in FIG. 12, after the inside of the vacuum chamber 76 is setto a vacuum state, the opening 46 (injection port) of the sealing member44 is brought into contact with the oil 52. As illustrated in FIG. 13,when the hermetically sealed state of the vacuum chamber 76 is releasedand the air is leaked, the oil 52 is filled into the empty cell 74(space surrounded by the sealing member 44) from the opening 46 of thesealing member 44. The oil 52 flows faster as the oil 52 has lowerviscosity.

According to this embodiment, when the oil 52 is injected into thedisplay region 48 from the opening 46 of the sealing member 44, the flowof the oil 52 can be weakened by the wall portion 60, and hence it ispossible to reduce damage on the shutter 14 (see FIG. 2) arranged in thedisplay region 48. Further, the wall portion 60 is simultaneously formedwith the spacer 54, the shutter 14, and the drive portion 38, and henceit is possible to avoid increase in the number of manufacturing steps.In this manner, the oil 52 is filled as illustrated in FIG. 14. Afterthat, as illustrated in FIG. 2, the opening 46 is closed with the endseal 50.

FIGS. 15 and 16 are views illustrating modified examples of the displaydevice according to the embodiment of the present invention.

In the example illustrated in FIG. 15, a wall portion 160 is formed soas to linearly extend between the opening 46 and the display region 48to pass a position interrupting the shortest path. The wall portion 160is formed only at this position, and does not surround the displayregion 48. At least the oil 52 (see FIG. 14) flowing in from the opening46 hits the wall portion 160 before flowing into the display region 48,and hence the above-mentioned effect can be achieved. Further, the wallportion 160 is formed continuously with a length exceeding the width ofthe display region 48. Therefore, the oil 52 flows around from thelateral side of the display region 48, with the result that the flowpath is set longer to decrease the flow velocity.

In the example illustrated in FIG. 16, a wall portion 260 extends alonga plurality of parallel straight lines, and parts of the wall portion260 extending along the respective straight lines include slits 266. Theslits 266 are formed in a staggered manner, and hence the oil 52 (seeFIG. 14) flows in a zigzag manner. With this, the flow path of the oil52 can be set longer to decrease the flow velocity. While there havebeen described what are at present considered to be certain embodimentsof the invention, it will be understood that various modifications maybe made thereto, and it is intended that the appended claims cover allsuch modifications as fall within the true spirit and scope of theinvention.

1. A display device, comprising: a pair of light transmissive substratesarranged at an interval; a sealing member which is brought into closecontact with opposed surfaces of the pair of light transmissivesubstrates, the sealing member comprising an opening and surrounding aspace defined by the pair of light transmissive substrates; an end sealfor closing the opening of the sealing member, thereby encapsulating thespace to form an encapsulation space; oil filled in the encapsulationspace; a spacer, which is arranged in the oil, for maintaining theinterval between the pair of light transmissive substrates; a lightshielding film formed on one of the pair of light transmissivesubstrates, the light shielding film comprising an aperture portion; ashutter arranged in the oil; a drive portion arranged in the oil, formechanically driving the shutter so as to control passage and blockingof light through the aperture portion; and a wall portion formed on atleast one of the opposed surfaces of the pair of light transmissivesubstrates, wherein the spacer, the shutter, and the drive portion arearranged in a display region for displaying an image depending onpresence/absence and intensity of the light passing through the apertureportion, wherein the wall portion comprises a part arranged at aposition interrupting a shortest path between the opening of the sealingmember and the display region, and wherein the wall portion is made of amaterial forming the spacer, the shutter, and the drive portion.
 2. Thedisplay device according to claim 1, wherein the wall portion is broughtinto close contact with the opposed surfaces of the pair of lighttransmissive substrates.
 3. The display device according to claim 2,wherein the wall portion is arranged so as to surround the displayregion, and wherein the wall portion comprises a slit formed at aposition except for the position interrupting the shortest path.
 4. Thedisplay device according to claim 2, wherein the wall portion is formedso as to linearly extend between the opening and the display region topass the position interrupting the shortest path.
 5. The display deviceaccording to claim 4, wherein the wall portion extends along a pluralityof parallel straight lines, and parts of the wall portion extendingalong the plurality of parallel straight lines, respectively, eachcomprise a slit.
 6. A method of manufacturing a display device,comprising: assembling an empty cell so as to comprise: a pair of lighttransmissive substrates arranged at an interval; a sealing member whichis brought into close contact with opposed surfaces of the pair of lighttransmissive substrates, the sealing member comprising an opening andsurrounding a space defined by the pair of light transmissivesubstrates; a spacer, which is to be arranged in oil, for maintainingthe interval between the pair of light transmissive substrates; a lightshielding film formed on one of the pair of light transmissivesubstrates, the light shielding film comprising an aperture portion; ashutter arranged in the space; a drive portion arranged in the space,for mechanically driving the shutter so as to control passage andblocking of light through the aperture portion; and a wall portionformed on at least one of the opposed surfaces of the pair of lighttransmissive substrates, the spacer, the shutter, and the drive portionbeing arranged in a display region for displaying an image depending onpresence/absence and intensity of the light passing through the apertureportion, the wall portion comprising a part arranged at a positioninterrupting a shortest path between the opening of the sealing memberand the display region; and injecting the oil into the empty cell fromthe opening of the sealing member, wherein the assembling of the emptycell comprises simultaneously forming the spacer, the shutter, the driveportion, and the wall portion in a plurality of processes comprisingforming of a thin film and etching, and wherein the injecting of the oilcomprises injecting the oil from the opening of the sealing member undera state in which an inside of the space is set to have an atmosphericpressure lower than an atmospheric pressure of an outside.